International Journal of Minor Fruits, Medicinal and Aromatic Plants. Vol. 4 (1) : 13-19, June 2018 Evaluation of chemical composition and assessment of antimicrobial activities of essential oil of lemongrass (Cymbopogon citratus (dc.) stapf) U. G. A.T Premathilake1, D. L. Wathugala2*, R. M. Dharmadasa3 1Department of Export Agriculture, Uva Wellassa University of Sri Lanka, 2Department of Crop Science, University of Ruhuna, Sri Lanka, 3Herbal Technology Division, Industrial Technology Institute, Colombo, Sri Lanka *Email:
[email protected] Received : 12.05.17 ; Revised : 18.07.17 ; Accepted : 31.07.17 ABSTRACT Use of synthetic antimicrobial agents raises harmful effects for environment and human health. Therefore, this study focused on analysis of the chemical composition and assessment of the antibacterial and antifungal activities of essential oil of lemongrass (Cymbopogon citratus (DC.) Stapf). The essential oil was extracted from fresh leaves of lemongrass by hydro-distillation technique. Chemical composition of essential oil was analyzed by Gas chromatography and Mass spectroscopy (GC-MS) and Citral (35.97%), â- Citral (26.5%), cis – Verbenol (26.3%) and Citral diethyl acetal (19.58%) were identified as main chemical compounds. Antifungal activity of essential oil was tested using Poisoned Food Technique. Essential oil of lemongrass possessed promising growth inhibitory effect on tested fungal strains. Total growth inhibition was observed in Fusarium spp., Penicillium spp. and Crysosporium spp. respectively for all four different concentrations (1,000, 5,000, 10,000 and 15,000 ppm) of essential oil and Colletotricum truncatum at 10,000 ppm and 15,000 ppm concentrations. Disk diffusion method was applied to assess the antibacterial activity of essential oil (25, 50, 75, and 100%) against 3 different pathogenic bacteria strains (Escherichia coli, Bacillus cerveius and Staphylococcus aureus).